1. Field of the Invention
The invention relates to the field of photography and, more particularly, to a photographic apparatus including an exposure counter for use therewith.
2. Description of the Prior Art
It is customary to provide photographic apparatus with an exposure counter so as to convey certain information to the user regarding the number of exposures which have been made or which remain in a film assemblage located within the photographic apparatus. Exposure counters generally include an indicia-bearing member having characters thereon which are sequentially presented at a viewing station, usually a window, in the apparatus for conveying this information to the user. Usually, the characters are sequentially changed by an indexing system coupled to a film advancing apparatus which in turn is manually operated by a hand crank located on the camera as shown in U.S. Pat. Nos. 2,608,922 and 2,552,275. Operation of the hand crank advances a film frame into position for exposure and simultaneously indexes the exposure counter to change the character present at the viewing station. Needless to say, manual operation of the crank leaves something to be desired. Further, many exposure counters are unduly complicated in construction and operation, and are often positioned in locations within the apparatus having limited accessibility, thereby making it more difficult to reset them to their starting position subsequent to the exposure of the last film unit or frame in the film assemblage. One solution proposed to improve the problem of resetting the exposure counter is described in U.S. Pat. No. 2,813,469, namely, an arrangement whereby opening the camera's door will automatically reset the camera's exposure counter to its starting position. However, opening the camera's door is not necessarily connected with the act of providing the camera with a fresh supply of film and therefore does not necessarily ensure that the counter will be properly oriented prior to the next exposure. For example, after one or more film units have been exposed, should the camera's door be opened for purposes of viewing the film container to ascertain if it is correctly positioned within the camera or for inspection of one of the components of the camera, such as the processing rollers in a camera of the self-developing type, the counter would be automatically reset thereby resulting in the exposure number of the counter being out of phase with the number of the next exposure.
U.S. Pat. No. 3,653,313 describes an exposure counter for use with a single-lens reflex camera which solves the problem of resetting the exposure counter by automatically resetting the camera's counter upon removal of an empty film container from within the camera. However, the exposure counter is coupled to a reflecting member or mirror and sequentially advanced in response to movement of the reflecting member between a lowered viewing position and a raised exposure position. In order to utilize the pivotal movement of the reflecting member to rotate the exposure counter, a relatively complex system including a plurality of pivotally mounted pawls and cam surfaces interact to accomplish the desired result of indexing the exposure counter as the reflecting member moves from the viewing position to the exposure position and back again. The exposure counter is automatically reset upon the removal of the empty film container from within the camera whereupon the resetting cycle is accomplished by the pawls and cam surfaces interacting in a reverse manner to release the exposure counter for rotation in a reverse direction into a starting position. Therefore, the indexing and resetting of the exposure counter is substantially dependent upon each member of the system being properly located and coupled to an adjoining member such that the previous movement of one member is sufficient to displace a second member in contact therewith, originating with the reflecting member operating to initiate movement of the counter in the indexing mode and a cantilevered spring the end of which displaces one of the pawls thereby enabling the exposure counter to reset itself in the starting position.
From the foregoing, it can be seen that there is a need for an exposure counter capable of conveying information regarding the number of exposures remaining within a camera to the user which uses fewer moving parts, is automatically reset upon the removal of an empty film container, and provides increased reliability and durability at reduced manufacturing costs.